The present invention is directed to an apparatus for spreading material, and in particular to a spreader vehicle that employs features such as double tipping, a parallel slope box floor configuration for improved material flow, a gate assembly providing enhanced material discharge from the box, a disc feed deflector that eliminates chute blockage design, a double disc spreader assembly, deflector plates providing easier maintenance and reduced material jamming, and removable chutes as part of the box for enhanced flexibility in carrying and spreading materials.
In the prior art, double tipping vehicles are well known. U.S. Pat. No. 4,141,591 is one example of such a vehicle.
Spreader vehicles are also known as exemplified in Smith""s U.S. Pat. No. 3,931,934. FIG. 1 of the Smith patent depicts a vehicle with a box that is forward tipping only to direct material onto spreader discs arranged in front of the vehicle drive wheels. Smith uses a sliding plate to control the discharge of the material from the box. With this design, the material discharged from the box supplies traction for the wheels when driving conditions may be hazardous. This patent is hereby incorporated in its entirety by reference.
The spreader vehicle of Smith is not without its disadvantages however. With the Smith box design, feed blockages often occur, thus interrupting spreading of material on a roadway or leaving a boxload of material that cannot be emptied. Feed blockages are often caused by the state of the material in the box. With ideal material, i.e., material of the proper size and moisture content, blockages do not generally occur. However, the material is many times oversized or in the form of lumps and crusts as a result of freezing. This oversized material then blocks the gates of the box or does not flow properly. If the material is inadequately prepared, it can compact in the box and cannot be discharged easily. Mixing of the material with snow may also lead to discharge problems. Further, the sliding plate design of Smith tends to be oriented in a level or horizontal position when forward tipping occurs, such an orientation not conducive to easy flow of material.
Another problem in prior art designs is the difficulty in spreading materials of different sizes and consistencies using a single box configuration. For instance, materials that are coarser may distribute and flow differently than materials that may be more slurry-like such as sludge.
As such, a need has developed to provide an improved spreader apparatus, particularly, for off-highway use. A need also exists to accommodate different types of materials for spreading with the same apparatus. In response to these needs, the present invention provides an improved spreader apparatus and method of spreading that overcomes the deficiencies in the prior art design.
Accordingly, it is a first object of the present invention to provide an improved spreading apparatus.
Another object of the present invention is a spreading apparatus that minimizes problems in material discharge.
A still further object of the present invention is a method of spreading material using one or more features of the inventive apparatus for improved material discharge.
One other object of the present invention is an apparatus that can be installed on an existing vehicle or manufactured as part of a new vehicle.
Yet another object of the invention is an apparatus and method of spreading material wherein the apparatus is used in an off-highway application, e.g., roadways that are used in the mining industry and the like.
One further object of the invention is a method of spreading material and an apparatus therefore that utilizes a box having removable chutes for material discharge. One or a pair of chutes is configured to facilitate the spreading of a desired charge of material.
Other objects and advantages of the present invention will become apparent as a description thereof proceeds.
In satisfaction of the foregoing objects and advantages, the present invention, in one embodiment, is an improvement over prior art spreader apparatus such as disclosed in the Smith patent noted above.
The Smith prior art spreader is equipped with a forward-only tipping box having a box floor and a diverter arranged on the box floor. The diverter forms a funnel-shaped travel path to a pair of openings. The material discharge is controlled by gates adjacent the openings. Once exiting the openings, the material enters a chute and falls onto a rotating disc for spreading.
In one embodiment of the invention, the box is both forward tipping and rearward tipping. The box may have a tailgate on a rearward end for rearward tipping, if desired.
In another embodiment, the diverter of the box is sectioned into two portions, one shaped like the prior art design and a second portion providing a travel path which allows for easier flow of material to the gate openings. The second section employs a pair of plates positioned forward of the termination the first diverter portion, the plates inclined towards each other and forming a travel path that is generally the same in cross sectional area for the length of the plates. In this way, the funneling of prior art design is avoided and material can more easily flow toward the gate openings. In a preferred embodiment the floor width in the second portion is about 6 feet wide, but other widths can be used.
Another feature of the invention is that the gates are each hinged to pivotally open rather than slide open as in the prior art. The gate is aligned generally with the plane of the box floor to enhance material discharge. Further, the gate has a grid or series of plates attached thereto, the plates channeling the material to the spreader discs as the material flows out the gate opening an along the gate. Although plates are shown, other grid configurations could be employed to channel the material as it exits the gates.
In yet another embodiment, deflector plates are arranged beneath and adjacent the gates. The deflector plates replace the prior art chutes and minimize jamming as well as provide for easier access to the spreading assembly components for maintenance. The deflector plates extend transversely of the vehicle length and track the width of the gate for material channeling. Using the grid on the gates with the deflector plates enhances the material discharge from the box.
Another embodiment of the invention includes using at least a pair of rotatable discs beneath the deflector plates. A pair of discs allows for wider gate openings. Further, the gate and grid configuration permits a wider flow of material exiting the box and the ability to use more than one disc. Using at least a pair of discs allows for changes in disc rotation directions and speeds and a greater variety of distribution patterns.
The forward tipping box also employs a cab guard, which pivots with forward tipping. The cab guard then both protects the cab during the spreading operation as well as during box loading.
In another embodiment, the invention entails a vehicle spreader box assembly for on off-road vehicle comprising a box body adapted to be mounted to an off-road truck, the box body having opposing sides, a floor, and a forward wall. The floor further comprises a diverter extending upwardly from the floor to form a pair of material flow paths between the diverter and each opposing side of the box. Each material flow path terminates in an opening in the box floor. The box body includes a pair of chutes, each chute having an inlet, a converging wall structure forming another material flow path, and an outlet of defined width. Each inlet is adapted to removably attach to a respective box floor opening.
Each chute includes a gate assembly, each gate assembly having a gate sized to cover the chute outlet. The gate is pivotal between a closed position and an open position, opening of the gate allowing material to be discharged from the box body.
The spreader box can be mounted on an off-road truck having a truck body. The truck body has one or more spreader devices positioned beneath each chute outlet for distribution of material in the box body.
A deflector plate can be positioned downstream of each gate of the removable chutes, and each gate can include a plurality of plates downstream of the gate to vertically channel material exiting each gate.
The off-road truck spreader vehicle can comprises a rear tipping mechanism adapted to tip the box body rearward, and/or a front tipping mechanism adapted to tip the box body forward. When using the front tipping mechanism, a pivotal cab guard is provided extending forward of a front end of the box body, the cab guard shielding a cab of the vehicle in the forward tipped position and a horizontal box body position.
The diverter and the opposing sides can form either a pair of converging material flow paths to each box floor opening, or material flow paths, wherein each path has a converging portion and a non-converging portion.
The vehicle spreader box assembly is adapted to employ a plurality of pairs of chutes, each pair having unique configurations to accommodate a particular type of material for spreading.
This embodiment also involves using the spreader vehicle features to efficiently spread materials of different sizes and consistencies. The method involves loading the material desired for spreading and discharging it by gate operation and, if desired box tipping. The removable chutes are selected based on the material to be discharged. After one spreading task, the chutes can be replaced with differently-sized chutes to spread a different material.